I read his paternal grandmother was that one saying she was there at the hospital for his birth in Kenya.
I missed the part about the hospital, but read that Obama's grandmother, half-brother, and half-sister said that he'd been born in Kenya.
The grandmother may be right, but the half-siblings were almost certainly too young to remember Obama's birth.
I guess the bigger stumbling block to believing this is why Obama Sr. would bring his pregnant new wife or girlfriend thousands of miles to where his first wife and disapproving father lived (or that he'd go back to Kenya just to show her the country and not visit his native village).